A new stem-neopterygian fish from the Middle Triassic (Anisian) of Yunnan, China, with a reassessment of the relationships of early neopterygian clades

A new stem-neopterygian fish, Louwoichthys pusillus, has been identified from Middle Triassic marine deposits in Yunnan, China. This small, tooth-adapted species, measuring up to 39 mm, is closely related to Luopingichthys and Ctenognathichthys, forming the newly described family Louwoichthyidae. The study introduces a novel order, Louwoichthyiformes, to resolve paraphyly in 'Perleidiformes' and supports its monophyly with derived cranial features. Louwoichthys is inferred as a scavenger, likely using its elongated teeth to manipulate prey. This research advances understanding of early neopterygian diversity and evolutionary relationships during the Anisian stage.

Xu, G.-H. (2020). A new stem-neopterygian fish from the Middle Triassic (Anisian) of Yunnan, China, with a reassessment of the relationships of early neopterygian clades. Zoological Journal of the Linnean Society, 191(2), 375–394. https://doi.org/10.1093/zoolinnean/zlaa053